Query String Parser

Parse query strings or URLs into JSON parameters.

What this tool does

Parse query strings or full URLs into structured JSON so you can inspect parameter values and repeated keys.

Tool interface

Input

Output

Example input

https://example.com/callback?state=abc&scope=read&scope=write

Example output

{
  "state": "abc",
  "scope": [
    "read",
    "write"
  ]
}

Step-by-step instructions

  1. Paste a query string or full URL.
  2. Click Transform to parse parameters.
  3. Review JSON output and copy it for debugging.

Common use cases

  • Debugging request payloads and encoded values quickly.
  • Generating development data and identifiers.
  • Validating text, URLs, timestamps, and structured content.

Useful for debugging redirects, callback URLs, and query parameter handling in frontend and backend code.

Common mistakes to avoid

  • Including malformed percent-encoded values.
  • Expecting fragment/hash values to appear as query parameters.
  • Assuming duplicate keys are collapsed to one value.

Frequently Asked Questions

Can Query String Parser parse full URLs?

Yes. It extracts and parses the query portion of a full URL.

How are duplicate parameters represented?

Duplicate keys are returned as arrays.

Can I parse strings starting with `?` only?

Yes. Raw query strings are supported.

What input format does Query String Parser expect?

Use the format shown in the example input on this page.

What does Query String Parser output?

It returns transformed output you can copy or download as `parsed-query.json`.

Why might Query String Parser return an error?

A common issue is: Including malformed percent-encoded values.

Does Query String Parser run in the browser?

Yes. Transformations are designed for in-browser usage so you can test and iterate quickly.

Can I copy or download results from Query String Parser?

Yes. You can copy the result or use the download action when file output is available.

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